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Review and Measurements of Chord Mojo DAC and Amp

oufloued

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Technically it should:
- the charge pump circuit on Mojo classic, is sufficient for charging, no more. its output is not clean enough. It relies on the battery itself for final smoothing.
- remember that the DAC side of all Chord products is single ended.
- The battery can supply current surges when required by the headphones, the charge circuit can not.
- on Mojo2 the PSU is upgraded because of the above since it has a desktop mode.
This has been discussed to death on Headfi. Some users have reported that taking the battery out does no harm, they'd been diing it for some time!
Scientificly, I can not see how that is possible.
important UPDATE:
after a few months powering the mojo 1 with removed battery via the charging usb slot i must confirm Ken Tajalli's assumptions.
it took me quite a while to notice, but in the end it was obvious the sound quality degraded to a level where i could tell no difference to the headphone output of my smart phone. also the chassis got quite warm, even hot (i helped with cooling fins on chassis' top, but that was quite a fragile "solution".)
now i modded the mojo applying a budget 7,5 V with maximum 2000 mA power supply directly to the battery slot internally. i simply used the JST jack/cables of the old worn out battery. also i had to hone down the chassis on the headphones side a little to allow for the two cables leading out of the unit (that was the easiest solution to me, as i want to keep this precious modjo anyway ;) - it sounds quite fine now to me. but i have to again burn in to it. let's see.
 

Jimster480

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important UPDATE:
after a few months powering the mojo 1 with removed battery via the charging usb slot i must confirm Ken Tajalli's assumptions.
it took me quite a while to notice, but in the end it was obvious the sound quality degraded to a level where i could tell no difference to the headphone output of my smart phone. also the chassis got quite warm, even hot (i helped with cooling fins on chassis' top, but that was quite a fragile "solution".)
now i modded the mojo applying a budget 7,5 V with maximum 2000 mA power supply directly to the battery slot internally. i simply used the JST jack/cables of the old worn out battery. also i had to hone down the chassis on the headphones side a little to allow for the two cables leading out of the unit (that was the easiest solution to me, as i want to keep this precious modjo anyway ;) - it sounds quite fine now to me. but i have to again burn in to it. let's see.
That is quite a bit of work! How come you didn't source a new battery?
 

oufloued

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I have one, he could have had it at cost.
I don't use the mojo under way. While traveling (mostly train) I fall back to using bluetooth headphones: simplicity over audiophile quality of sound.
The mojo, I bought it 2 hand, sounds well enough in my modest main system.
In this situation, I find an ever dying battery to be not appropriate. Therefore the "mod" (no big deal at all, I'm amateur honer and solderer!).

The next step will be: powering the modjo with a laboratory linear adjustable power supply (which also could be the end of modjo - but: I'm curious how much voltage/current does it appreciate? The power light now is still green, had been blue with fully charged battery ;)
 

Ken Tajalli

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I don't use the mojo under way. While traveling (mostly train) I fall back to using bluetooth headphones: simplicity over audiophile quality of sound.
The mojo, I bought it 2 hand, sounds well enough in my modest main system.
In this situation, I find an ever dying battery to be not appropriate. Therefore the "mod" (no big deal at all, I'm amateur honer and solderer!).

The next step will be: powering the modjo with a laboratory linear adjustable power supply (which also could be the end of modjo - but: I'm curious how much voltage/current does it appreciate? The power light now is still green, had been blue with fully charged battery ;)
Mojo prefers a decent SMPS. Linear PS is not good for Mojo, others have tried.
8V , 200mA is sufficient, so even a decent 2W one will do nicely.
Fit as big a cap inside, now that you have taken the battery out.
Get a 9V SMPS, use a diode on +Vcc to drop it to just over 8V.
That'll do.
 

Deckard01

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Jun 11, 2023
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Hello does it worth if can buy mojo 1 for 160 dollars or a dongle at this price range is better? Such as DC04 PRO or M1P that I was looking at as a budget and good option.

I care only for audio quality for Headphones such as HD600 and K701 and also mostly used with laptop.

Any suggestion would be really helpful!

Thanks for all
 

Ken Tajalli

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Hello does it worth if can buy mojo 1 for 160 dollars or a dongle at this price range is better? Such as DC04 PRO or M1P that I was looking at as a budget and good option.

I care only for audio quality for Headphones such as HD600 and K701 and also mostly used with laptop.

Any suggestion would be really helpful!

Thanks for all
Mojo is better for sure.
Only issue with a used one is battery life.
Can easily be replaced.
$160 is a bit steep though.
 
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